But Kam, 84, has said he fired only after Clemensen already was dead, and German prosecutors dropped a murder case against him in 1971 for lack of evidence.

However, the Danish government released autopsy reports in 1997 that said all eight shots on Clemensen came at the same time. A Danish court ruled in 2004 that Kam could be tried in Denmark.

One of the suspects, Flemming Helweg-Larsen, was convicted of murder and executed in Denmark in 1946. Another suspected gunman, Jorgen V. Bitsch, disappeared after the war.

Denmark had previously asked for Kam to be extradited, but a German court rejected the request because Kam was a German citizen. However, Danish authorities decided to try again after a legal change in Germany, said Lene Roesen, a legal expert at Denmark's Justice Ministry.

German forces invaded neighboring Denmark on April 9, 1940, and occupied the Scandinavian country for five years.